[vtkusers] vtkImageFFT and vtkImageButterworthLowPass

[Pascale Beliveau]

Hi,

   I have a question concerning FFT transforms. Can it be applied to a 3D
image?

I am trying to use the butterworth filter of vtk. The volume is fed to
vtkImageFFT and then I want to apply the butterworth filter. The problem is
the image is empty right after I feed it to vtkImageFFT (size=0,
extent=[0,-1,0,-1,0,-1]). I converted my intensity values to float since I
read that FFT cannot support other types than float or double.

Can anyone help me with this? What else could be a problem with vtkImageFFT?

Thanks in advance,
Pascale

PS: here is my code for reference:


vtkImageFFT * FFT = vtkImageFFT::New();
FFT->SetDimensionality(3);
FFT->SetInput(VtkImage);


vtkImageButterworthLowPass * LPFilter = vtkImageButterworthLowPass::New();
LPFilter->SetInput(FFT->GetOutput());
LPFilter->SetOrder(2);
LPFilter->SetXCutOff(10000);
LPFilter->SetYCutOff(10000);
LPFilter->SetZCutOff(10000);
LPFilter->ReleaseDataFlagOff();

vtkImageData * Result = LPFilter->GetOutput();
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